Rsx是一种转基因RNA,在X染色体不活化过程中具有Xist样性质
Jennifer Grant1, Shantha K Mahadevaiah, Pavel Khil
1MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW71AA, UK.
Nature
|June 23, 2012
概括
研究人员在雌性有袋动物中发现了一种新型RNA,RSx (RNA-on-the-silent X). 这种RNA对于X染色体无活化至关重要,这是哺乳动物对基因剂量补偿至关重要的过程.
科学领域:
- 遗传学 是一个遗传学.
- 发展生物学 发展生物学
- 进行比较基因组学.
背景情况:
- 哺乳动物的雌性 (XX) 沉默一个X染色体用于基因剂量平衡.
- 欧瑟利亚X染色体的非激活依赖于Xist非编码RNA.
- 在有袋动物中X染色体失活的机制在很大程度上仍然是未知的.
研究的目的:
- 为了研究袋动物X染色体失活的机制.
- 为了确定涉及 marsupial X染色体失活的潜在RNA分子.
主要方法:
- 他研究了有袋动物Monodelphis domestica. 这种动物的研究.
- 鉴定并描述了一种新型RNA,Rsx (RNA-on-the-silent X).
- 研究了女性体和生殖细胞中的Rsx表达模式.
- 通过将Rsx转基因整合到小鼠胚胎干细胞中进行功能研究.
主要成果:
- Rsx是一种大型,重复丰富的RNA,仅在雌性有袋动物中表达.
- Rsx从不活跃的X染色体中转录并覆盖.
- 在X染色体都活跃的雌性生殖细胞中,Rsx表达被沉默.
- Rsx转基因整合诱导了小鼠细胞中cis中的基因沉默.
结论:
- Rsx表现出与袋鼠X染色体失活中的作用相一致的特性.
- 研究结果表明Rsx可能是 marsupials中的Xist的功能模拟物.
- 这一发现使得在哺乳动物进化过程中对X染色体失活的比较研究成为可能.
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